Daily necessities at home are growing in numbers due the continuous improvement of living standards. Sorting out the items could be a serious trouble in many situations since scattering the items about will further exaggerate the trouble. Therefore, shelves are being more widely used in daily life these days. A shelf to place and sort the daily necessities would be needed for the increasing types of the items. It would be helpful to provide a flexibly and simply designed shelf to facilitate sorting of daily necessities. Such a shelf would be especially beneficial for having daily necessities ready to find and access.
Fixed shelves existing in markets are generally divided into an on-site type, a wall-hanging type and a ceiling type. Since the shelves are fixed, it is difficult to satisfy the requirement for ease of access and the requirement for reducing occupied space simultaneously. In prior arts, a type of shelves would be fixed to a wall. Mounting the shelf at a lower height enables easier access to the placed items for users, but requires more usable home space. Mounting the shelf at a higher height allows the user to pass under without occupying usable home space, but presents difficulty in accessing placed items. A pulley and a motor can be employed to achieve rising and declining of a ceiling type shelf. When a user needs to access an item, he or she can lower the shelf. The user can raise the shelf and pass under the shelf in order to save home space. This configuration enables rising and declining of the shelf by fixing three or four positions on the shelf with ropes. Instability during the rising or declining of the shelf could cause the shelf to waggle and results in insecurity such as collision or even dropping of items on the shelf. The ceiling type shelf also incurs difficulties during installation. A user is usually unable to install the shelf alone. Costs for installing the shelf are likely to increase.